Left tackle Eugene Monroe left the practice field on a cart Wednesday after getting hit in the head during drills. Team doctors were checking him for a possible concussion, and coach Mike Mularkey said the results would determine whether Monroe plays in Friday night's preseason game at New Orleans. Kickoff is set for 8 p.m.

Guard Will Rackley missed the preseason opener because of a high-ankle sprain, is still wearing a walking boot and will be sidelined at least another week. Backup guard Jason Spitz is out at least a month because of a foot injury, and reserve center is John Estes is likely out for the season because of a knee injury.

"Got to be able to adapt, just got to be able to push forward with what you've got," guard Uche Nwaneri said. "It's not easy, but it's not supposed to be easy. ... We've got a lot of guys. We've got a good number of guys who have been here. We all understand the mentality. Overcoming the injury bug like that depends on how prepared your backups are."

The offensive line was expected to be one of Jacksonville's strongest positions this season. The line helped pave the way for Maurice Jones-Drew to lead the NFL in rushing last season.

All five starters returned, including right tackle Eben Britton, who played just 11 games the last two seasons because of injuries.

But with Rackley out, the Jaguars moved Britton to left guard and inserted second-year player Cameron Bradfield in at tackle. After Monroe went down, Bradfield moved to the left side and former practice squad player Daniel Baldridge went in at right tackle. That combination could end up starting against the Saints.

"It is what it is. Guys go down," Britton said. "You've got to be able to have somebody step up and produce the way a starter would. That's the way we prepare: Everybody is a No. 1 and that's the way you have to think."

Injuries are common in the trenches, so much so that the Jaguars have never gone an entire season with the same starting five offensive linemen. They came close in 2006, with one starter missing one game, and set the franchise record for rushing yards in a season (2,541).

Keeping the same five "would be great, but that's not really always realistic," Britton said. "You've just got to roll with what you've got."

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